The federal agency overseeing offshore energy exploration announced Wednesday that it would require companies operating offshore to provide additional information about the potential risks and safety precautions in their drilling plans. Regulators have failed to demand such disclosures even in the aftermath of the BP oil spill, according to evidence obtained by The Washington Post.

The Minerals Management Service exempted more than half a dozen drilling operations in the Gulf of Mexico from a detailed environmental review -- including the site of the Deepwater Horizon explosion and seven projects in the accident's wake -- after subjecting them to a pro-forma checklist, according to documents released by the Interior Department.

The agency gave all eight operations "categorical exclusions" from the National Environmental Policy Act -- a waiver that freed oil and gas companies from completing a lengthy environment impact statement. The checklist does not mention the prospect of a blowout, does not address the impact of an operation's noise on marine mammals and minimizes an oil spill review for any drilling site within four miles of national marine sanctuary.

"This is a process that's designed to give approval, rather than one to identify a sensitive area," said Richard Charter, senior marine policy advisor for the advocacy group Defenders of Wildlife, after reviewing the documents. "In the Gulf of Mexico, they only have a rubber stamp for categorical exclusions, saying 'Go ahead.'"

Bob Abbey, who is serving as acting director of MMS, said Wednesday in a statement that even those companies who have received environmental waivers will have to resubmit their development and exploration plans before drilling any new wells.

"The moratorium on deepwater drilling that Secretary Salazar has ordered is a prudent step that will allow time for the Presidential Commission to complete its review of the BP Deepwater Horizon oil spill and for immediate safety and environmental reforms to be implemented," Abbey said. "Pulling back exploration plans and development plans and requiring them to be updated with new information is consistent with this cautious approach and will ensure that new safety standards and risk considerations are incorporated into those planning documents."

In response to a request from The Washington Post, Interior officials provided redacted versions of the reviews MMS conducted before approving eight separate exploration plans in the gulf. Several environmental groups--including the Defenders of Wildlife, the Southern Environmental Law Center and the Center for Biological Diversity--are suing Interior on the grounds that it failed to make drilling companies comply with federal environmental laws.

They list a few dozen "trigger" criteria that would prompt a more extensive environmental assessment, such as whether the project will involve "new or unusual technology" and if it's within four miles of the Flower Garden Banks national marine sanctuary or within three miles of the Stetson Bank sanctuary. But for the most part, the review document appears to provide a relatively easy path to obtaining a federal environmental waiver.

For example, an Interior Department manual that took effect May 27, 2004 states that MMS should not issue categorical exemptions to drilling taking place in "relatively untested deep water, or remote areas." But on May 3 the agency approved an Anadarko well going more than 9,000 feet deep. In the section that refers to "initial [development operations and coordination documents] for processing facilities in [water depths greater than] 400 meters," the box "no" was checked.

"I don't understand how this relatively deep water section is checked as a no," said Catherine Wannamaker, a senior attorney at the Southern Environmental Law Center.

And in the case of the April 13 waiver granted to BP's revised exploration plan for Mississippi Canyon 252, agency officials said they made the determination "with analysis," but don't specify what that analysis is, beyond the checklist.

Layla Hughes, senior program officer for the World Wildlife Fund's Arctic policy, said the cursory review process undermines the intent of the National Environmental Policy Act, which is only supposed to be waived when an activity is expected to have little or no environmental impact.

"Were this kind of approach actually permissible under NEPA [National Environmental Policy Act], every agency would be doing it, and NEPA would be completely gutted," Huges wrote in an e-mail.

The White House Council on Environmental Quality is leading a review of these waivers, in concert with Interior officials. Kieran Suckling, executive director of the Center for Biological Diversity, said they should "shut down" the exemptions when it comes to offshore drilling.

"MMS is making baby steps in the right direction, but it is not enough to require more information from the oil companies," Suckling said. "MMS needs to formally revoke all 400 environmental waivers given out in the past 18 months and redo each and every decision."